The current MicroStation V8i SELECTseries update 1, 08.11.09.357, is certified for use on Windows 8.

The current AECOsim Building Designer V8i SELECTseries update 1, 08.11.09.376, is not certified but will run on Windows 8 so may be worth trying out, but is definitely not ready for production use on Windows 8. A Windows 8 certified version is due in the New Year.